@book{cullum2002lanczos,
  author = {Cullum, J.K. and Willoughby, R.A.},
  interhash = {cfc97672c78c590391fc6f731d48ddc2},
  intrahash = {b6fa6a375178396d472af2006fb21fc8},
  publisher = {Society for Industrial Mathematics},
  title = {{Lanczos algorithms for large symmetric eigenvalue computations: Theory}},
  url = {http://scholar.google.de/scholar.bib?q=info:zshJq2GVHO8J:scholar.google.com/&output=citation&hl=de&ct=citation&cd=0},
  year = 2002
}

@book{cullum2002lanczos,
  author = {Cullum, J.K. and Willoughby, R.A.},
  interhash = {82c29b42b778abfb29f21caa940fc1f7},
  intrahash = {2966d91a1166afb969cdffb879d6f305},
  publisher = {Society for Industrial Mathematics},
  title = {{Lanczos algorithms for large symmetric eigenvalue computations: Documentaion and Listings Original Lanczos Codes}},
  url = {http://scholar.google.de/scholar.bib?q=info:zshJq2GVHO8J:scholar.google.com/&output=citation&hl=de&ct=citation&cd=0},
  year = 2002
}